DESCRIPTION (Applicant's abstract verbatim): The objective of this proposed research is to construct a prototype neutron microscope capable of imaging biological maternal. By using compound refractive lenses recently developed by Adelphi Technology microscopy is possible with imaging distances in the order of a few meters. Neutron microscopy can be a valuable complement and extension of already mature light, x-ray and electron imaging techniques. Unlike these other sources, neutron propagation in matter is defined by strong neutron-nucleus interaction. Neutrons can provide a means to probe into materials with a completely different "light" allowing visualization of objects otherwise concealed. Biological molecules are ideal for imaging with neutrons, as their hydrocarbon constituents would provide excellent image contrast. Thicker, unstained, unfixed, in vivo samples may be imaged with neutrons since they are less affected by absorption than other sources thus, reducing artifacts created by sample preparation. Also, achievable resolutions of neutron microscopy surpasses those attained with visible light and x-rays, down to few Angstroms making it possible to directly image viruses and genes. The potential for successful development of the prototype imaging system is very high because our preliminary experiment with compound refractive lenses has demonstrated thermal neutron collection and focusing. The research will proceed by optimizing the design of these lenses for imaging and, then, experimentally demonstrating image magnification of biological materials. Neutron microscope designs will include commercially available compact neutron sources for clinical and laboratory use. PROPOSED COMMERCIAL APPLICATION: The development of neutron lens of short focal length would be truly revolutionary since such a lens could be utilized in a large number of applications related to imaging biological materials. Neutron microscopy will permit high-resolution, high-contrast imaging of soft tissue. Unlike x-ray imaging, which achieves contrast with high atomic number atoms, neutron imaging will give contrast with low atomic number materials.